diff --git a/src/calcwidget.cpp b/src/calcwidget.cpp
index cde1d8c..89ab230 100644
--- a/src/calcwidget.cpp
+++ b/src/calcwidget.cpp
@@ -13,6 +13,7 @@ CalcWidget::CalcWidget(QWidget *parent) :
         ui(new Ui::CalcWidget)
 {
     ui->setupUi(this);
+    m_ctx = MainWindow::getContext();
 
     ui->imageExchange->setBackgroundRole(QPalette::Base);
     QPixmap pm(":/assets/images/exchange.png");
@@ -106,21 +107,15 @@ void CalcWidget::toComboChanged(const QString &data) {
 }
 
 void CalcWidget::initCrypto() {
-    if (this->m_ctx == nullptr)
-        this->m_ctx = MainWindow::getContext();
-
     this->initComboBox();
 }
 
 void CalcWidget::initFiat() {
-    if(this->m_ctx == nullptr)
-        this->m_ctx = MainWindow::getContext();
-
     this->initComboBox();
 }
 
 void CalcWidget::initComboBox() {
-    if(m_comboBoxInit || this->m_ctx == nullptr) return;
+    if(m_comboBoxInit) return;
     QList<QString> marketsKeys = AppContext::prices->markets.keys();
     QList<QString> ratesKeys = AppContext::prices->rates.keys();
     if(marketsKeys.count() <= 0 || ratesKeys.count() <= 0) return;
diff --git a/src/calcwidget.h b/src/calcwidget.h
index 8bd6c50..95af5f9 100644
--- a/src/calcwidget.h
+++ b/src/calcwidget.h
@@ -31,7 +31,7 @@ public slots:
 
 private:
     Ui::CalcWidget *ui;
-    AppContext *m_ctx = nullptr;
+    AppContext *m_ctx;
     bool m_comboBoxInit = false;
     void initComboBox();
     bool m_changing = false;
diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index 64bd35e..f7bdf51 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -37,14 +37,14 @@ MainWindow * MainWindow::pMainWindow = nullptr;
 MainWindow::MainWindow(AppContext *ctx, QWidget *parent) :
     QMainWindow(parent),
     ui(new Ui::MainWindow),
-    m_ctx(ctx),
-    m_aboutDialog(new AboutDialog(this)),
-    m_windowCalc(new CalcWindow(this))
+    m_ctx(ctx)
 {
     pMainWindow = this;
     ui->setupUi(this);
 
     m_windowSettings = new Settings(this);
+    m_aboutDialog = new AboutDialog(this);
+    m_windowCalc = new CalcWindow(this);
 
     // light/dark theme
     m_skins.insert("Native", "");
diff --git a/src/settings.cpp b/src/settings.cpp
index 5175eb9..1b61554 100644
--- a/src/settings.cpp
+++ b/src/settings.cpp
@@ -12,10 +12,9 @@ Settings::Settings(QWidget *parent) :
         ui(new Ui::Settings)
 {
     ui->setupUi(this);
-    this->setWindowIcon(QIcon("://assets/images/appicons/64x64.png"));
+    m_ctx = MainWindow::getContext();
 
-    if(m_ctx == nullptr)
-        m_ctx = MainWindow::getContext();
+    this->setWindowIcon(QIcon("://assets/images/appicons/64x64.png"));
 
     ui->tabWidget->setTabVisible(2, false);
     ui->tabWidget->setTabVisible(4, false);
diff --git a/src/settings.h b/src/settings.h
index 845c79b..e4ac3f1 100644
--- a/src/settings.h
+++ b/src/settings.h
@@ -47,7 +47,7 @@ private:
 private:
     void setupSkinCombobox();
 
-    AppContext *m_ctx = nullptr;
+    AppContext *m_ctx;
     Ui::Settings *ui;
 };
 
diff --git a/src/widgets/tickerwidget.cpp b/src/widgets/tickerwidget.cpp
index c601d1c..364859c 100644
--- a/src/widgets/tickerwidget.cpp
+++ b/src/widgets/tickerwidget.cpp
@@ -15,6 +15,7 @@ TickerWidget::TickerWidget(QWidget *parent, QString symbol, QString title, bool
     m_convertBalance(convertBalance)
 {
     ui->setupUi(this);
+    m_ctx = MainWindow::getContext();
 
     // default values before API data
     if (title == "") title = m_symbol;
@@ -29,7 +30,7 @@ TickerWidget::TickerWidget(QWidget *parent, QString symbol, QString title, bool
     connect(AppContext::prices, &Prices::fiatPricesUpdated, this, &TickerWidget::init);
     connect(AppContext::prices, &Prices::cryptoPricesUpdated, this, &TickerWidget::init);
     if (convertBalance)
-        connect(MainWindow::getContext(), &AppContext::balanceUpdated, this, &TickerWidget::init);
+        connect(m_ctx, &AppContext::balanceUpdated, this, &TickerWidget::init);
 }
 
 void TickerWidget::init() {
diff --git a/src/widgets/tickerwidget.h b/src/widgets/tickerwidget.h
index b0b8055..7ffb63f 100644
--- a/src/widgets/tickerwidget.h
+++ b/src/widgets/tickerwidget.h
@@ -34,6 +34,7 @@ private:
     Ui::TickerWidget *ui;
     QString m_symbol;
     bool m_convertBalance;
+    AppContext *m_ctx;
 };
 
 #endif // TICKERWIDGET_H